1. Field of the Invention
The present invention relates to the production of fertilizer from brewery cleaning solutions.
2. Description of Background Art
The manufacture of fertilizer from waste materials is well known.
Japanese patent 50149136 relates to a process for treating sewage for fertilizer production, in which caustic alkali is used to dissolve fats, proteins, etc. Following filtration, the filtrate is mixed with lime slurry, and the precipitate that forms is then used as a fertilizer.
Japanese patent 79020425 to Katakura Chikkarin Co., Ltd., discloses a composition that is prepared by diluting an alcohol-fermentation molasses waste liquor, then dissolving urea, water-soluble ammonium salts, nitrate, sulfate, chloride, and phosphoric acid therein while stirring--and finally reacting the mixture with caustic potash.
In the case of brewery wastes, in particular, it is known (according to Japanese patent 89027038) that the addition of a small amount of a distillate derived from Ternstroemiaceae plants to beer lees can produce a fertilizer having reduced odors.
Japanese patent 58208191 discloses a soil activator composition by adding a Bacillus culture and an Actinomycetes strain culture to a protein nitrogen source, such as dry beer yeast waste, and a humic acid containing material, such as peat or lignite.
U.S. Pat. No. 4,579,579 discloses a process for the preparation of slow-release fertilizer comprising the steps of:
(a) grinding a first volume of peanut hulls to a particle size of 1/32 to 1/2 inch and a second volume to 3/8 to 1/2 inch, PA1 (b) treating the first volume of hulls with an equal volume of 2N nitric acid for 30 minutes at 121.degree. C. and 15 p.s.i. pressure to extract and solubilize the liquid material from the hulls, PA1 (c) adding one volume of one normal solubilized sodium hydroxide to two volumes of the second volume of peanut hulls and heating and stirring the mixture until the nutrients are solubilized, PA1 (d) heating the second volume of peanut hulls and sodium hydroxide with steam and at a temperature of 121.degree. C. and pressure of 15 p.s.i. for 30 minutes to open the fibers of the hulls, PA1 (e) adding fertilizer nutrients, such as commercially available potash, super phosphate, or other source of phosphate and ammonium nitrate or other source of nitrogen, to liquid waste material from the beer brewing industry containing either live or autolyzed yeast or other biological waste material, PA1 (f) drying the heat-treated peanut hulls, whereby the fibers of the hulls close, entrapping the nutrients and the waste material, PA1 (g) soaking the dried, impregnated hulls with the lignincontaining liquid from step (b), and PA1 (h) drying the peanut hulls. PA1 draining the brewing equipment of liquid brewing product; PA1 treating residual brewing products remaining in those portions of the drained brewing equipment containing carbon dioxide with a cleaning solution comprising phosphoric acid; PA1 treating residual brewing products remaining in those portions of the drained brewing equipment not containing carbon dioxide with a cleaning solution comprising caustic potash; PA1 the residual brewing products comprising atoms selected from the group consisting of nitrogen, carbon, and mixtures thereof; PA1 then, neutralizing the cleaning solution comprising phosphoric acid with the cleaning solution comprising caustic potash; PA1 whereby a fertilizer solution comprising potassium phosphate and the treated residual brewing products is formed. PA1 combining brewery caustic potash cleaning solution with brewery nitrogen- or phosphorus-containing acid cleaning solution in mutually neutralizing amounts to produce a fertilizer solution comprising a potassium salt having nitrogen-containing, organic, brewing materials contained therein. PA1 combining spent brewery caustic potash cleaning solution with spent brewery phosphoric acid cleaning solution in mutually neutralizing amounts to produce a fertilizer solution comprising potassium phosphate having nitrogen-containing, organic, brewing materials contained therein. PA1 draining the brewing equipment of liquid brewing product; PA1 treating residual brewing products remaining in those portions of the drained brewing equipment containing carbon dioxide with a cleaning solution comprising phosphoric acid; PA1 treating residual brewing products remaining in those portions of the drained brewing equipment not containing carbon dioxide with a cleaning solution comprising caustic potash; PA1 the residual brewing products comprising atoms selected from the group consisting of nitrogen, carbon, and mixtures thereof; PA1 then, neutralizing the cleaning solution comprising phosphoric acid with the cleaning solution comprising caustic potash; PA1 whereby a fertilizer solution comprising potassium phosphate and the treated residual brewing products is formed.